Had it with the return caps!

[chris142]

I have been fighting my leaking caps since it got cold 3 weeks ago. It's always one on the passengers side. Usually the 2nd one back. I bought the kit from Napa (That took a week for them to get me the right kit). I put them on and they leaked. I ordered some #111 Fuel O-Rings. Those lasted a couple of days then the 3rd one back leaked.

I went out this morning and replaced all 4 caps on that side with the rest of the new ones and installed new Orings again. Fired it up and now fuel is pouring out of the rear 90* one! This is unreal and completly frustrating!

Waiting on a PM from type4 now.

 

[tbrumm]

Yeah, it is frustrating and I feel you pain. I fought this for quite a while too. The Guys here pointed me to checking the caps for flashing from the molding process, which cuts the orings as you put them on. finally bought new caps from Ford (previously had the Dipaco caps) and then put in Viton orings I bought from McMaster-Carr and my return system has good for a while now. I am sure you have followed the suggested install procedures listed on the Forum here in many threads such as lubing the orings, installing the too oring first and then carefully sliding the lower oring over that, making sure the caps snaps over the orings and is seated, etc, etc,etc.The only other thing I can suggest is making sure the return line back to the tank is not somehow restricted making the fuel stay in the return lines and build up a little pressure. Or, perhaps placing an oring between the top of the cap and the fuel line nut to place a little pressure on the cap to hold it down. I think Everybody fights with this issue from time to time and its frustrating before you get it all worked out, but eventually you will.

 

[icanfixall]

Both Mel and Russ have the best return line kits. This forum has found the ebay and most other sources are crappy kits. This message is not directing you to buy from forum members. Its pointing you in a direction to solve your return line issues. The facts speak for themselves.

 

[chris142]

I have lubed the orings with everything from Grease to diesel fuel to oil. I went back out there just now and changed the o-rings again. still have fuel pouring out of it. I changed the cap again and it seems to not be leaking right now. You mentioned them snapping down? Mine don't click or snap they just push on. I had wondered if I could put something on there to push that cap down under that nut. I think I'll try that if it does it again

 

[chris142]

Hopefully type 4 can get me some good ones a very soon

 

[ah1988ford]

I have lubed the orings with everything from Grease to diesel fuel to oil. I went back out there just now and changed the o-rings again. still have fuel pouring out of it. I changed the cap again and it seems to not be leaking right now. You mentioned them snapping down? Mine don't click or snap they just push on. I had wondered if I could put something on there to push that cap down under that nut. I think I'll try that if it does it again

I have found that a 5/8 open end wrench fits perfectly over the top of the plastic caps,and you can apply even pressure down on the wrench and it helps to seat the caps in there place without slipping and violently twisting the plastic caps lol. My #1 cap has been giving me hell I finally orderd some viton 111 orings off of ebay... hopefully they fix it.

You can tell when they are seated its a pretty firm click or snap feeling, not so much of a noise.

 

[G. Mann]

I found some nice silicone grease that is used for swimming pool O rings. [pool supply stores have tubes of it for cheap] I lube up the O rings and the caps. O rings slide on and seat much nicer, and the caps go on easily without dragging on the O rings which can cut of shift them out of their lands. Don't need much.. a "little dab will do'ya. But assembly is much easier and I've gone 5 years now.. no problems..

Which reminds me.. it's about time, just because, to pop in a fresh set..

 

[chris142]

Ya these napa caps don't snap or lock. I bought some washers just now at the hardware store. Gunna try that next

 

[icanfixall]

Use an extra or used o ring on top of the plastic caps. The nut will push it down to make the cap press down like its supposed to fit.

 

[theguruat12]

Use an extra or used o ring on top of the plastic caps. The nut will push it down to make the cap press down like its supposed to fit.

X2. I've heard that from many members now and I did it the second time I redid my o-rings. Hold them in place much better.

I happen to just use grease gun grease for my o-rings. Works for me.

 

[chris142]

Just sent Russ some $$$ for the good caps and O-Rings. Now I just gotta make due till they show up

 

[thx997303]

This return line system is garbage. I wish someone with the tools and equipment would design and sell a better designed system.

And in my opinion, aluminum caps of the original design aren't the answer, but I seem to be in the minority.

My driver side rear cap is leaking now, and since this is the fifth time I've had to fix them, I'm sick and tired of it.

 

[riotwarrior]

Make sure you inspect the INSIDE of the cap and any casting flaws that may be present the little plastic ridge from a casting line so to speak needs to be gently sanded or cut out carefully. If there is a small piece of flash that nicks the O ring you will get leaks...regardless of how many times you put new O rings on

Russ has some very nice cap sets. I know I"ve got one here to go on soon.

The engine it is going on had a new set of caps and what looks like O rings installed and I saw that ONE is/was a leaker even though it's all new..previous owner installed mind you but new none the less.

May be doing a Tech 101 on return line caps and one on Oil cooler too since both are getting done!

JM2CW

Al

 

[chris142]

The inside of the napa caps is smooth. If they are suposed to snap then there's nothing to make them snap and stay put. I put thin washers between the nut and the cap. What was happening is that the caps work up and uncover the little holes. The washers keep the caps from moving up

 

[ADV]

What I was seeing in the plastic caps is they are not very round. The best ones were the original gray ones. Also the black replacement caps were a bit bigger.